Check the contact’s orientation marks or labels
Compare it to the manufacturer’s diagram
Look for the side that should face up, out, or toward the wire
Verify the terminal shape matches the mating part
Confirm the locking tab or latch is on the correct side
Make sure the contact sits flush in the housing
Check whether the wire entry and mating end are reversed
Inspect if the contact pin or socket is facing the wrong direction
Compare it with a correctly installed contact
Test fit the connector to see if it will seat properly